Mechanical release



June 1948- L. P. FRIEDER Er Al. 2,442,632

MECHANICAL RELEASE Filed Deo. 6, 1944 4 Sheets-Sheet l Jun@ i948- L. P.FRIEDER Er AL *2,442,682

MECHANICAL RELEASE Filed Dec. 6, 1944 4 Sheets-Sheet 2 INVENTORSfawn/Pz? 959/505? June 1, 1948. L. P. FRIEDER ET An.

MECHANICAL RELEASE 4 Sheets-Sheet 5 Filed Dec. 6, 1944 June l, 1948. L,P FRlEDER [.1- AL 2,442,682

MECHANICAL RELEASE 4 Sheets-Sheet 4 Filed Dec. 6, 1944 NN. Y EN 5m n REN Y mw @km mp6 ,H .Mm A NT i WQ Y NN l bw .nu Mm,

etented June l, 1948 MECHANICAL RELEASE Leonard P. Frieder, RockvilleCentre, and Walter S. Finken, Brooklyn, N. Y.; said Finken assigner tosaid Frieder Application December 6, 1944, Serial No. 566,944

(Cl. 28d-33.15)

7 Claims.

This invention relates to mechanical releases and it is la purpose ofthe invention to provide a device so constructed and arranged to connectoppositely pulling elements and to effect their immediate separation atthe will of an operator, or as the result of the external application offorce on the device. An application of the invention is for towing aglider. In this capacity the device is attached to a glider andreleasably engages a bob on a tow line.

Another object of the invention is to provide a device for towing atarget and for eiiecting the release of a used target and itsreplacement by a new target. For attaining this object the `device isadapted to be opened for applying it labout a cable fastened to a towingairplane and to slide along the cable and replace a like mechanicaldevice and assume the function of towing a new target.

Further and other objects of the present invention will be hereinafterset forth' in the accompanying specification and -claims anddemonstrated by the drawings which show by way of illustration apreferred embodiment and the principle of our invention and what we nowconsider the best mode in which we have contemplated applying thatprinciple. Other embodiments of the invention employing the sameprinciple may be used and structural changes made as desired by thoseskilled in the art within the spirit of the appended claims and withoutdeparting from the present invention.

In the drawings,

Fig. 1 is a side view of a mechanical release temploying the principlesof the present invenion;

Fig. 2 is a view of the mechanical device illustrated in Fig. 1 turned90 on its axis;

Fig. 3 is a longitu-dinal section of the mechanical device taken on line3 3 of Fig. 2;

Fig 4 is a cross-section on line 4 4 of Fig. 2;

Fig. 5 is a cross-section on line 5--5 of Fig. 2;

Fig. 6 is a cross-section on line Ii-S of Fig. 2;

Fig. 7 is a sectional View similar to that shown in Fig. 3 with themechanical bob-engaging means displaced to non-engaging positions;

Fig. 8 is a sectional View taken on the plane of line 13-4 of Fig 2, butwith the halves of the device separated;

Fig. 9 is a longitudinal view of the device opened as in Fig. 8;

Fig. l0 is a longitudinal section through a bob.

It is very important in the operation of gliders that release means beprovided between the glider and the towing plane whereby the glider maybe 2 Y f instantly released at the will of the operator. The connectingand releasing device of the present invention includes two principalmembers I0 and II which are displaceable in respect to each other foreffecting th'e immediate release of a tow line I2. Member I0 is providedwith means for attaching the member to a glider and it also carriesadjustable mechanical means which are engageable with a bob or otherdevice I3 fastened to the tow line I2. This member transmits the pullbetween the tow line and glider,

The means for attaching the member I0 to a glider may be variouslyformed Iand in the embodiment of the device illustrated in the drawingsconsists oi a pair of lugs I4, I5, extending from one end of member I0and having openings therein for receiving bolts I6, I 1, which arefastened to a stanchion or brackets I 8 and I9 carried by the glider.The other end of member I9 is provided with pairs of lugs 2U, 2I bywhich' the mechanical means for engaging the bob is supported.

The mechanical bob-engaging means comprise a pair of levers 22, 23,-eachlever being supported for pivotal movement uppn bolts 24, 25 passingthrough the pairs of lugs 2U, 2I, respectively. These levers arearranged to pivot in a diametrical plane and are provided with jaws 26,2l capable of being moved towards and away from each other. In theirmost advanced position towards each other, they engage a bob I3 securedto and by which the tow line I2 is held fast. The jaws are preferablycrescent-shaped to engage a large area of the bob.

Levers 22 and 23 are provided with arms'28, 29, respectively, whichcooperate with member I I for holding the jaws in bob-engaging positionwhen member II is in the position relative to member Il) shown in Figs.1, 2, 3 and 4. Member Il is carried by and is slidable with respect tomember IB and is provided with a ange or shoulder 3l! which is integraltherewith and adapted to underlie the arms 28 and 29vof the levers forrestraining them against movement from their bob-engaging positions.

Member II is provided with a nger piece SI by which the glider pilot mayretract member II to the position shown in Fig. '7 for releasing thelevers from their locked position and to effect release of the tow line.In order to facilitate the disengaging operation anti-friction means isprovided between the levers and shoulder 30 in the form of rollers 32,33, carried by larms 28 and 29, respectively.

So as to lprevent unintentional displacement of member I I with respectto member I0, means coacting between the two members are provided whichh'ave the eifect of holding the two members in set positions relative toeach other. This result is attained by spring washers 31, 38 which areheld in place by screws 39 and 4B, respectively, engaged in member I.The shanks of these screws pass through elongatedslots 41|, 42 whichdetermine the length of travel of member II over member IE), When memberII is in leverlocking position, as shown in Figs. 1, 2, 3 and 4, thescrews engage one end of the elongated slots 4I and 42. The springwashers 31 and 38 effect a frictional drag against the unintentional`displacement of member II with respect to member I0, but it will beunderstood that the tension provided by the spring washers is adjustableand is set so as to provide not any more restraining force than can beeasily overcome by an operator applying force to nger piece 3|.Immediately -upon -displacing member II, jaws 26 and 21 are expanded asa result of the lateral forces exerted upon the jaws bythe bob under theinfluence of the -pull of the towline.

It is convenient to construct members I5 and II as sleeves, andpreferably with a central bore 43 having a-diameter-suiiici'ently greatto accommodate -the passage therethrough of a Ibob, although ?for`glider towing purposes it is advantageous that vthe forward end ofmember AII) be hollowed at least to such a degree as to contact thegreatest girth of the bob as at 43a, Fig. 3. lIhe bob is thereby held'from lateral movement, andthe effect of the jaws 26 and 21 is to bearaxially on the bob almost entirely.

Sleeve member I`I is extended forwardly of the jaws a distance at leastas great as the permissible length 4of travel of member I I relative tomember In and its forward end is provided with a -nose 45 with a roundedannular opening 46 whereby the angular deiiection ofthe line I2 islimited. Cricumstances sometimes make it desirable that the pilot of-atowing plane be able to cast off a tow and this may ybe accomplished byproviding the pilot of the towing plane with a weighted Ymessenger thatcan be placed on the tow line and allowed to slide down towards the tow.When the messenger strikes nose 45 the levers 22 and `23 are releasedfrom their bobengaging positions and the tow is cast oif.

Projection e4 is provided with `a pair of openings 41, 4'8 through whichVthe `levers of jaws 26 and 21 extend. The parts Vmay be constructed ofmetal, such as steel, or of such other `material as will .provid-e therequired strength.

While the mechanical release so far described is well suited fordisconnecting gliders from a tow line, the invention lillustrated in thedrawings is embodied in such a form as to be useful for towing a targetKand for replacing a device holding a target being towed. For serving inthis capacity the two sleeve members I and Il are separable 'into twosections .and have central bores of sufcient diameter for enabling thepassage therethrough of a bob or other similar device 'attached to a towline. The device may be opened, as shown in Figs. 8 and 9, to be placedabout a towing lineextending rearwardly from an airplane. Hinges 53 4and5I are attached to the two sections of the outer sleeve Il. When thedevice is closed, the two sections of the outer sleeve mem-ber arelocked together by a bolt 52, which passes through holes in lugs 53, 54in one `of the sections of sleeve member Il and a hole in tongue 55which is supported by a pin -55 carried Y 4 by the other section ofsleeve member I I, Figs. 1 and 2.

Each section 51, B, of the inner sleeve member i5 is fastened to itsadjacent outside section of outside sleeve member Il by means of thescrews 39 and 43, respectively, Fig. 3. It will be appreciated that theinside sections 51 and 58 may be independently displaced longitudinallyof the sections of the outside vsleeve member 'II when the device isopen. In order to bring these sections into proper registry with eachother for Vclosing the device, pins 59 and 65 and register- Y ing holes5I and 62 are provided.

When this device isemployed for towing a target, -the-device'is `held bythe bob I3 in the manner illustrated in Fig. 3. The target is attachedto -lugs Ill and i5 by 4means of lines engaged in the eyes in lugs I4and I5. After the target has been shot away by gun re or has been sodamaged as to render it useless, it Ibecomes desirable to east it oli`without reelingin the tow line. An operator in the airplane selectsanother ='device 'to which a 'new target is attached. The static line of'the package containing the new target and the supporting line of the'new target are secured to the eyes 'in lugs I4 and I5. This device isopened inthe manner illustrated iin Fig. 9, placed about the 'tow `linewith its 'nose =45 in the "direction of vthe Vanchored lend 'ofthe towline, and then closed and locked in closed position, by means of bolt52. Before releasing the device and its attached target, the 'operatorsees that sleeve II is extended to the position shown in Figs. 1, 2 and3 so that the jaws 2'6, 21 of levers 22, 23 Vare held in bob-engagingposition. The compression Iin springs 31 and 3'8 is 'adjusted to theextent necessary V.to hold sleeve I`I -in extended position during Ythedescent of 'the device along the tow line, and care is taken to makesure 'that the compression will not prevent-sleeve `Il from beingdisplaced by another vsimilar device or messenger in a subsequenttarget-releasing operation. The Vdevice is then allowed to slide d'ownthe tow line. When'it strikes'the nose `45 of the device carrying theused target it will cause displacement of sleeve II of .the 'latterdevice and free its levers 22 'and -23 from bob-engaging position. Thereleased device will then be cast off with its used target and thereplacing device will assume its position with its levers in engagementwith the freed bob. Upon thearrest of the substitute device the staticline frees the wrapped target which is thereafter towedby'its sustainingcord.

The bob illustrated-in the drawings consistsof a member 63 having a borethrough which the tow line lI2 passes. The tow line is-secured to member63 by a, pin-64. A cap-65 is in threaded engagement with member-63 andencloses the lloop at the end of the line and at tthesame timepreventsdisplacement of pin 64 axially of itself and from disengaging relationwith the loop.

What is claimed is:

1. lA mechanical release for holding'and releasing a bob attached to aline comprising engaged inside'and outside members slidablewith respectto each other, the outside member being in the form of a sleeve having aportion extending 'beyond one end of the other member, means coactingbetween said members for limiting 'the sliding movement of said outsidesleeve member inthe direction of its extending portion, a Vpair lofflevers pivotally mounted oppositely each other on said inside member,said ylevers having arms movable through openings insaid outsidesleeve'member and jaws on said arms movable towards and away from eachother as the levers are pivoted, means on said outside member forholding said jaws towards each other in bob-engaging position when saidmembers are located with respect to each other by said irst-namedmovement-limiting means, means :cooperating with said members forproviding resistance to their relative movement, and means carried bysaid inside member for fastening the same .to an anchor.

2. A mechanical release for holding and releasing a bob attached to aline, comprising members engaged for linearly sliding with respect toeach other, one of said members carrying a pair of levers pivotallysupported opposite each other, said levers being symmetrically placedabout the common longitudinal axis of said members and having jaws forengaging a bob located with its axis on the longitudinal axis of saidmembers,

means on the other of said members for releasably holding said leverswith said jaws disposed towards each other in bob-engaging Position whensaid members are so set with respect to each other as to locate saidholding means in contact with said levers, and means frictionallycooperating between s'aid members for normally preventing relativesliding movement of said members while holding said levers inbob-engaging position but permitting relative sliding movement thereofto automatically release said levers from bob-engaging position byapplication of external force upon one of said members Ito eiTectsliding of one of said members from its set position relative to theother member and the accompanying release of said levers whereupon thebob is immediately freed.

3. A mechanical release for holding and releasing a bob attached to aline, comprising members engaged for sliding linearly with respect toeach other, a pair of levers pivotally supported opposite each other onone of said members, said levers having jaws symmetrically disposed atopposite sides of the longitudinal axis of said members when engaging abob and adapted to be spread apart by the camming action of ythe engagedbob unless said levers are restrained in a bob-engaging position, meanson the other of said members for holding said levers with said jawsdisposed towards each other in a bob-engaging position, and meansfriotionally cooperating between said members for preventingunintentional displacement of said members with respect -to each otherwhereby said members are held against displacement for holding saidlevers in bob-engaging position and said frictionally `operating meansmay be overcome and said members displaced to release said levers forreleasing the bob as a result of application of an external force on oneof said members along the axis of support of said bob.

4. A mechanical release for holding and releasing a bob attached to aline, comprising a loadcarrying member, a sleeve mounted ythereon forlongitudinal displacement along said load-carrying member, a pair oflevers pivotally mounted on said member and disposed with jawssymmetrically located with respect to the axis of said member forengaging a bob when said jaws are in their position of closest approach,means on said sleeve for holding said levers and jaws in bob-engagingposition whereby said bob is releasably held by said jaws, said meansbeing slidable with said sleeve for eiecting release of said levers, andmeans frictionally cooperating with said member and said sleevetemporarily to hold them against Vunintentional displacement relative toeach other and to permit relative displacement of said sleeve over saidmember to release said levers from bobengaging position uponVapplication of force applied externally Ito said sleeve in a directionlongitudinally of its axis.

5. A mechanical release for holding and releasing a bob attached to aline, comprising a pair of sleeves, one of said sleeves being inside theother and having a bore of suiicent diameter to permit the passage of abob, lever means mounted on said last-named sleeve for engaging a bobcentrally disposed with respect to its bore, means carried by the otherof said sleeves for holding said lever means in bob-engaging .positionwhen said sleeves are in a predetermined position with respect to eachother and whereby said lever means are relieved from restraint ofmovement from bob-engaging position when said sleeves are displaced fromsuch predetermined position with respect to each other, and meansopposing unintentional displacement of the sleeve members from suchpredetermined position with respect to each other, said last-named meansbeing adapted to be overcome to permit relative displacement of saidsleeve members as a result of the application of external force upon oneof said sleeve members.

6. A mechanical release for holding and releasing a bob attached to laline, comprising a pair of telescoping sleeves slidable with respect toeach other unless restrained, the inner of said sleeves having a bore toaccommodate a bob for passage therethrough and said sleeves beingcomposed of sections separable on lines extending longitudinally of thesleeves so that the sleeves may be opened to receive a line attached toa bob and closed to encompass said line, means for holding said sectionstogether in the form of sleeves, a pair of levers oppositely mounted forpivotal movement on one of said sleeves, said levers being provided withjaws for engaging a bobcentrally located on the axis of said sleeves,means on the other of said sleeves for holding said levers and jaws inbob-engaging position against the separating eiiort of said bob actingto spread said jaws, and means cooperating with said sleeves forrestraining unintentional displacement of said sleeves with respect toeach other and responsive to impact on one of said sleeves to permitrelative displacement of said sleeves to release said levers frombob-engaging position.

7. A mechanical release for holding and releasing a bob attached to aline, comprising a pair of inside and outside sleeves slidablelongitudinally with respect to each other, said inside sleeve having abore to accommodate the passage of a bob longitudinally therethrough,each of said sleeves being composed of two sections connected togetherand longitudinally separable whereby the sleeves may be opened for theinsertion of a line within the bore of the inner sleeve, means retainingadjacent inside and outside sections of said sleeves in nestedrelationship when the sleeves are parted, means for holding said sleevesin telescoping relationship when said sections are joined as sleeves,mechanical means carried by said inside sleeve and provided with movablejaws for engaging a bob centrally disposed with respect to the bore ofsaid inside sleeve, means on said outside sleeve for engaging saidmechanical means to hold said jaws in bob-engaging position against thespreading action of a bob engaged by said jaws, and means cooperatingwith both of said sleeves for preventing unintentional displacement ofsaid sleeves with respect to each other and .-adapted ato .permitdisplacement .nf Lsaid '-:outside :sleeve with :respect :to said insidesleeve -as ia. .re- .sult of-.impactupon the outsidesleeve toreleasesaidemovable -jaws zfrom bob-engaging position.

LEONARD TP. FEEDER. WALTER .:S. FINKEN.

.REFERENCES CITED y Thelfollowing references are vo'f record in the "lefof this "patent: 30

Number UNITED "STATES PATENTS Name Date Sinclair Jan. 3, 1899 PearenApr. 16, 1918 Lamkey Mar. 25, 1930 Foulk Aug. 28,1934

Drescher Aug. 29, -1944

